code: def get_or_create(session_uuid: str):
      cpu_key = CPUIndex.get(session_uuid)
  
      if not cpu_key:
          c = CPUModel()
          c.save()
          CPUIndex.set(session_uuid, c.key)
  
          cp = CPUPreferencesModel()
          cp.save()
          CPUPreferencesIndex.set(session_uuid, cp.key)
  
          return CPUAnalysis(c)
  
      return CPUAnalysis(cpu_key.load())
  
imports: from typing import Dict, Any
  from fastapi import Request
  from fastapi.responses import JSONResponse
  from labml_db import Model, Index
  from labml_db.serializer.pickle import PickleSerializer
  from labml_app.logger import logger
  from labml_app.enums import COMPUTEREnums
  from ..analysis import Analysis
  from ..series import SeriesModel, Series
  from ..series_collection import SeriesCollection
  from ..preferences import Preferences
  from ..helper import get_mean_series
label_desc: Use image node_id 4 for calling the CPUAnalysis obj's underlying member method code with example usage: obj.get_or_create(session_uuid) and returns: CPUAnalysis, CPUAnalysis